If I can't heat my house, how do I stop damp?

[babysoupdragon2]

We live in a 1930s semi.

Every winter we have huge issues with condensation on the windows, I have to do a daily window vac otherwise it spreads to the walls. This is despite ventilating the rooms well. No other damp causes.

The only thing we've found to help is to not let the temperature drop below about 15 overnight. But there's no way we will be able to pay for this this year.

Anyone have any suggestions?

I'm guessing that the night caps were made out of sponge?

We got the largest meaco dehumidifier a few years ago and it is amazing. It was an expensive purchase (I think it wasn't far off £300?!) but the house feels so much warmer and no more mould! We keep it on the landing and keep the doors ajar. Opening windows in the morning and letting the bed air also helps. Our heating is never set above 15 degrees and we only have it on twice a day.

This will be an issue for us too. Just to add I have read that the best way to ventilate the house is to open all the windows for just 5 minutes 2-3 times a day. Long enough for damp air to leave but not long enough for the walls to get cold is the idea. But do it frequently. But yes last year the heating always came on for a bit afterwards (we had it on all day at 18 as we were working from home). I'm not sure I want that this year because of yhe cost so we may need to just be cold. I wonder about turning it down to 16 or 17 in the day?

Fitting external insulation to our semi 12 years ago was a complete game changer.
Despite having great windows and ample loft insulation, we used to have terrible condensation and damp. External insulation has sorted it and of course had a very positive impact on our heating bills.
I bang on about the incredible benefits of external insulation all the time; if it is at all within one's financial reach I'd absolutely consider it. We spent all our savings on it at the time, and have definitely made that back in saved energy costs since. Our main motivator at the time was to reduce our carbon footprint, and it feels great that this is a 'passive' way of doing this.
We periodically use a 12l Ebac dehumidifier in our uninsulated conservatory during the winter, which is effective. During lockdown I occasionally found myself having to dry washing indoors, and the Ebac kept humidity down in the whole house.

No idea if it's any good but I saw somewhere online someone had a long oblong vase on the windowsill filled with white cat litter and fake succulent plants on top . I was going to give it a try in the winter if I can find something suitable .

I suspect that most people who are struggling to afford to heat their homes can’t pay £thousands to have external insulation.

15 degrees is your condensation point. Basically warm air will hold moisture until it hits something cooler- your windows. The only way to prevent condensation is to prevent a surface reaching the dew point - at which the water vapour in the air will condense.

An adult will lease something like close to a litre of water vapour per 24 hours so there will always be water vapour in your home including more when you cook and shower. I’m afraid if you can’t heat the house then a dehumidifier is your alternative- but these too take energy.

Wipe the windows dry with a cloth every morning. Leave them open just half a centimetre all the time if you can.

In my student days we used to leave bowls of salt on the window ledges which absorbed the water.
I remember it was quite effective.
We did reuse the salt by drying it out in the oven if we were already cooking something

Having lived in one which was poorly insulated, a dehumidifier is your friend. But it costs money to run. It was also a 'well ventilated' house because of the amount of gaps in the windows and doors.

Loft insulation would help, and check all your gutterings as ours leaked down the outside wall causing it to be constantly cold and damp. But as a PP has stated, this is expensive. We rented, the cold damp condensation was one of the reasons we moved, the heating bill was ridiculous and we ran the dehumidifier all day.

A dehumidifier will definitely help, probably two for each floor.

Is your chimney blocked off? People often put draught stuff in the chimney to keep houses warm but they’re often the main source of ventilation and air circulation by way of their design.

Have you checked that the insulation in the loft isn’t blocking any ventilation?

As general advice (altho you probably already do this) remove unnecessary soft furnishings in the damp tooms. So if it is a child's room - no teddies or cushions or rugs. Pack away summer clothes in boxes and put in the loft which should be drier. Leave your winter clothes with plenty of room to air. If you have breathing difficulties anyway the least soft furnishings the better.

Also if you have beds and fabric sofas near windows or against external walls, move them away - at 20cm to let air circulate round the room when you can open the windows in the daytime.

When I was a girl our single-glazed windows used to run with condensation. We wiped them with a weak bleach solution to stop mildew. Once my bedroom went mildew too so we bleached that too, let the area air, left to fully dry and then ultimately repainted the area in summer.

Actually it costs £1.06 a day to run.... www.sust-it.net/energy-calculator.php

Select tariff:
UK: Price Cap (April 2022)
Or:

Energy Calculator
Energy consumption:
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Time in use:
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Cost of electricity: £1.06

It is in bedrooms even with windows open all night? I have never experienced this, that is very bad. If you own the house, I would consider trying to find a more long term solution such as ventilation bricks? Obviously when money allows.

Condensation won't form in a very warm house because the temperature dries it out.

It also won't form in a very cold house because there isn't a differential between a warm area and a cold area. It forms when warm wet air hits a colder surface, eg a window or a mirror in the bathroom after you e had a shower.

It's the middling warm house that have the biggest problem as they are warm enough to have a differential temperature but too cold to dry the damp air

Also, use the extractor fan when cooking, they don't just take away smoke and grease but steam too so it is whisked away before settling on your walls and windows.

We had a similar issue with condensation in our 20yr old house. Windows running with condensation every morning. We had a Drimaster Positive Input Ventilation (PIV) system installed in the loft 2 years ago and problem solved. It costs about 2p or 3p a day to run so cheaper than the dehumidifier I was using, and also having to empty, every single day.
Also check your loft insulation too. If it’s covering vents then that will cause condensation to form.

www.thespruce.com/diy-dehumidifier-5104638

I found the above which might be helpful to those with a smaller budget that would mean not being able to afford a dehumidifier, I doubt any are perfect but if they can help then they are worth it.

Succulents in each window has helped massively with the condensation I used to get on the bedroom windows. I’ve only ever watered them twice when we had the massive heat wave.

I bought a dehumidifer this year, and it is amazing how much water it sucks out of the bedroom in a short time... In my head, I imagined it would dry it out and that would be that. I don't really understand how to use it to best effect!

@TooMuchToDoTooLittleInclination

windows open for an hour in the morning. Dehumidifier turned off then!

we have Meaco dehumidifiers (20 litres?) and they all need emptying once a day in winter. In summer we don’t use them and have the windows open all the time. We no longer get condensation (or ice) on our windows in winter.

I use the unibond Aero 360 dehumidifier thing.
You don’t need to plug it in but you do need to change the refills.
They work very well and I have one in every room and if you shop around you can get good deals on the refills.

Also keeping the windows open as PPs have said and using a window vac as you say.

We tried those and the refill needed changing after about a day!

We have these in our caravan but I don't see why they wouldn't work in houses, they pick up so much water. They are refillable with the crystals you can buy separately so a more budget option than a dehumidifier.
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